\scalebox{0.8}{
\begin{forest}
slot/.style={rectangle,minimum width=9mm, minimum height=9mm},
filled/.style={fill=lightgray},
mid/.style={circle, radius=1mm},
[{},mid,for tree={draw, grow=south}
  [{},mid,edge label={node[midway,left] {0}}
    [{},mid,edge label={node[midway,left] {0}}
      [{},mid,edge label={node[midway,left] {0}}
        [{$0$},slot,edge label={node[midway,left] {0}}]
        [{$1$},slot,edge label={node[midway,right] {1}}]
      ]
      [{},mid,edge label={node[midway,right] {1}}
        [{$2$},slot,edge label={node[midway,left] {0}}]
        [{$3$},slot,edge label={node[midway,right] {1}}]
      ]
    ]
    [{},mid,edge label={node[midway,right] {1}} 
      [{},mid,edge label={node[midway,left] {0}}
        [{$4$},slot,edge label={node[midway,left] {0}}]
        [{$5$},slot,rectangle,filled,edge label={node[midway,right] {1}}
            [{\footnotesize $1010...$},  l=2mm, rectangle, draw=none, edge=dotted]
        ]
      ]
      [{},mid,edge label={node[midway,right] {1}}
        [{$6$},slot,edge label={node[midway,left] {0}}]
        [{$7$},slot,edge label={node[midway,right] {1}}]
      ]
    ] 
  ]
  [{},mid,edge label={node[midway,right] {1}}
    [{},mid, edge label={node[midway,left] {0}}
      [{},mid,edge label={node[midway,left] {0}}
        [{$8$},slot,filled, edge label={node[midway,left] {0}}
            [{\footnotesize $1000...$}, l=2mm, rectangle, draw=none, edge=dotted]
        ]
        [{$9$},slot,edge label={node[midway,right] {1}}]
      ]
      [{},mid,edge label={node[midway,right] {1}}
        [{$10$},slot,edge label={node[midway,left] {0}}]
        [{$11$},slot,edge label={node[midway,right] {1}}]
      ]
    ]
    [{},mid,edge label={node[midway,right] {1}} 
      [{},mid,edge label={node[midway,left] {0}}
        [{$12$},slot,edge label={node[midway,left] {0}}]
        [{$13$},slot,filled,edge label={node[midway,right] {1}}
            [{\footnotesize $1011...$},  l=2mm, rectangle, draw=none, edge=dotted]
        ]
      ]
      [{},mid,edge label={node[midway,right] {1}}
        [{$14$},slot,edge label={node[midway,left] {0}}]
        [{$15$},slot,edge label={node[midway,right] {1}}]
      ]
    ]
  ] 
]
\end{forest}
}